Posted 3/4/2010

Hi,
i was wondering if anyone could give me some help in taking star trails.
I was out tonight for the first time and got some frustrating results. I was doing 20 minute shutter speeds at F5.6 with an ISO of 400. I keep getting colour distortion in the images and the sky comes out a purple, orange type colour, i tried for 10 minutes but still got colour distortion in the corners. What am i doing wrong? Is there a camera set up that anyone can recommend that would help me get started? That i can then tailor to the need of any particular situation.
Thanks for reading this, im sorry its so long!
Ash